||0.76x reduced risk of CKD for C allele
||1.25x Increased Risk of CKD for T allele in Icelandic study
23andMe blog each G at rs4293393 decreased the odds of chronic kidney disease by 24%. Approximately 18% of people with European ancestry have at least one G at this SNP. 
DeCode reports that the T allele of rs4293393 is associated with kidney stones and chronic kidney disease.  This SNP may also be associated with susceptibility to gout, hypertension, and diabetes. [PMID 20686651]
[PMID 19959715] Uromodulin Levels Associate with a Common UMOD Variant and Risk for Incident CKD
[PMID 20686651] Association of Variants at UMOD with Chronic Kidney Disease and Kidney Stones-Role of Age and Comorbid Diseases
[PMID 20222955] A meta-analysis of genome-wide data from five European isolates reveals an association of COL22A1, SYT1, and GABRR2 with serum creatinine level.